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Message-Id: <1433266205-24513-1-git-send-email-lczerner@redhat.com> Date: Tue, 2 Jun 2015 19:30:03 +0200 From: Lukas Czerner <lczerner@...hat.com> To: linux-ext4@...r.kernel.org Cc: Lukas Czerner <lczerner@...hat.com> Subject: [PATCH v3 1/3] ext4: Verify block bitmap even after fresh initialization If we want to rely on the buffer_verified() flag of the block bitmap buffer, we have to set it consistently. However currently if we're initializing uninitialized block bitmap in ext4_read_block_bitmap_nowait() we're not going to set buffer verified at all. We can do this by simply setting the flag on the buffer, but I think it's actually better to run ext4_validate_block_bitmap() to make sure that what we did in the ext4_init_block_bitmap() is right. So run ext4_validate_block_bitmap() even after the block bitmap initialization. Also bail out early from ext4_validate_block_bitmap() if we see corrupt bitmap, since we already know it's corrupt and we do not need to verify that. Signed-off-by: Lukas Czerner <lczerner@...hat.com> --- v2: nothing changed v3: nothing changed fs/ext4/balloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 955bf49..cd6ea29 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -369,7 +369,7 @@ static void ext4_validate_block_bitmap(struct super_block *sb, struct ext4_group_info *grp = ext4_get_group_info(sb, block_group); struct ext4_sb_info *sbi = EXT4_SB(sb); - if (buffer_verified(bh)) + if (buffer_verified(bh) || EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) return; ext4_lock_group(sb, block_group); @@ -446,7 +446,7 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) unlock_buffer(bh); if (err) ext4_error(sb, "Checksum bad for grp %u", block_group); - return bh; + goto verify; } ext4_unlock_group(sb, block_group); if (buffer_uptodate(bh)) { -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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